Differential c-fos expression in the nucleus of the solitary tract and spinal cord following noxious gastric distention in the rat

c-Fos has been used as a marker for activity in the spinal cord following noxious somatic or visceral stimulation. Although the viscera receive dual afferent innervation, distention of hollow organs (i.e. esophagus, stomach, descending colon and rectum) induces significantly more c-Fos in second order neurons in the nucleus of the solitary tract and lumbosacral spinal cord, which receive parasympathetic afferent input (vagus, pelvic nerves), than the thoracolumbar spinal cord, which receives sympathetic afferent input (splanchnic nerves). The purpose of this study was to determine the contribution of sympathetic and parasympathetic afferent input to c-Fos expression in the nucleus of the solitary tract and spinal cord, and the influence of supraspinal pathways on Fos induction in the thoracolumbar spinal cord. Noxious gastric distention to 80 mmHg (gastric distension/80) was produced by repetitive inflation of a chronically implanted gastric balloon. Gastric distension/80 induced c-Fos throughout the nucleus of the solitary tract, with the densest labeling observed within 300 microns of the rostral pole of the area postrema. This area was analysed quantitatively following several manipulations. Gastric distension/80 induced a mean of 724 c-Fos-immunoreactive nuclei per section. Following subdiaphragmatic vagotomy plus distention (vagotomy/80), the induction of c-Fos-immunoreactive nuclei was reduced to 293 per section, while spinal transection at T2 plus distention (spinal transection/80) induced a mean of 581 nuclei per nucleus of the solitary tract section. Gastric distension/80 and vagotomy/80 induced minimal c-Fos in the T8-T10 spinal cord (50 nuclei/section), but spinal transection/80 induced 200 nuclei per section. Repetitive bolus injections of norepinephrine produced transient pressor responses mimicking the pressor response produced by gastric distension/80. This manipulation induced minimal c-Fos in the nucleus of the solitary tract and none in the spinal cord. It is concluded that noxious visceral input via parasympathetic vagal afferents, and to a lesser extent sympathetic afferents and the spinosolitary tract, contribute to gastric distention-induced c-Fos in the nucleus of the solitary tract. The induction of c-Fos in the nucleus of the solitary tract is significantly greater than in the viscerotopic segments of the spinal cord, which is partially under tonic descending inhibition, but is not subject to modulation by vagal gastric afferents. Distention pressures produced by noxious gastric distention are much greater than those produced during feeding, suggesting that c-Fos induction in the nucleus of the solitary tract to noxious distention is not associated with physiological mechanisms of feeding and satiety. The large vagal nerve-mediated induction of c-Fos in the nucleus of the solitary tract following gastric distension suggests that parasympathetic afferents contribute to the processing of noxious visceral stimuli, perhaps by contributing to the affective-emotional component of visceral pain.     

Modular implementation of efficient self-checking checkers for the Berger code

A technique for designing efficient checkers for conventional Berger code is proposed in this paper. The check bits are derived by partitioning the information bits into two blocks, and then using an addition array to sum the number of 1's in each block. The check bit generator circuit uses a specially designed 4-input 1's counter. Two other types of 1's counters having 2 and 3 inputs are also used to realize checkers for variable length information bits. Several variations of 2-bit adder circuits are used to add the number of 1's. The check bit generator circuit uses gates with fan-in of less than or equal to 4 to simplify implementation in CMOS. The technique achieves significant improvement in gate count as well as speed over existing approaches.     

Potentially avoidable hospitalizations: inequalities in rates between US socioeconomic groups

OBJECTIVES: The National Hospital Discharge Survey (NHDS) was used to evaluate potentially avoidable hospital conditions as an indicator of equity and efficiency in the US health care system. METHODS: With the use of 1990 data from the NHDS, the National Health Interview Survey, and the census, national rates of hospitalization were calculated for avoidable conditions by age, race, median income of zip code, and insurance status. RESULTS: An estimated 3.1 million hospitalizations were for potentially avoidable conditions. This was 12% of all hospitalizations in 1990 (excluding psychiatric admissions, women with deliveries, and newborns). Rates of potentially avoidable hospitalizations were higher for persons living in middle- and low-income areas than for persons living in high-income areas, and were higher among Blacks than among Whites. These class and racial differences were also found among the privately insured. Differences among income and racial groups for persons aged 65 and over were not significant. CONCLUSIONS: Inequalities in potentially avoidable hospitalizations suggest inequity and inefficiency in the health care delivery system. Avoidable hospital conditions are a useful national indicator to monitor access to care.     

Interrelations of social support measures: Theoretical and practical implications.

To obtain a clearer picture of what constitutes social support, we conducted three studies to compare measures of different conceptions of social support. Relations of these instruments to various personality measures were also investigated. Subdividing the construct into discrete functions did not add to the sensitivity of the indices. Measures of received support and support networks were not strongly related to most of the perceived available support measures. Interview and questionnaire approaches were similar in the information they evoked about close supportive relationships. The results suggest that measures of perceived available support, regardless of the way the instruments attempt to break down the construct, generally assess the extent to which an individual is accepted, loved, and involved in relationships in which communication is open. Psychometric characteristics of the measures were associated with differential sensitivity over the range of supportive relationships. The theoretical implications of the findings are discussed with emphasis on the common core underlying social support indices. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Deficits in discriminated learning remain despite clearance of long-term persistent viral infection in mice

Mice persistently infected with lymphocytic choriomeningitis virus (LCMV) exhibit impaired learning ability. In this report, we determined whether clearance of the virus was associated with restoration of behavioral function. Neonatal Balb/cByJ mice were persistently infected with LCMV and tested as adults in a nonconditional spatial discrimination task. The presence of viral proteins in neurons was confirmed immunohistochemically and infectious virus was quantified in the blood by plaque assay. LCMV-infected adult mice made more errors in a Y-maze avoidance task compared to sham-inoculated controls. After the initial behavioral analysis, infected and control mice received a dose of cytotoxic T-lymphocytes sufficient to clear virus from these mice. Following complete clearance of the virus, mice were re-tested in the behavioral task, 5 months after the original test. No reversal of the learning deficit was seen following viral clearance; mice that had been cleared of the virus and those that remained persistently infected behaved similarly. These data indicate that persistent LCMV infection of the CNS lasting up to 7 months results in discriminated learning impairments that are not reversed by subsequent anti-viral immunocytotherapy.     

Thoracoscopic pleural tent

Lung volume reduction has been performed in patients with advanced emphysema to relieve dyspnea and improve exercise tolerance. Median sternotomy and video-assisted thoracoscopy have been proposed as equally adequate approaches; however, prolonged postoperative air leakage is the most prevalent complication in all series. For this reason, on the basis of the experience achieved with the median sternotomy approach, buttressing of the suture line with different materials and techniques for space reduction have been proposed. We describe a technique to create a pleural tent after thoracoscopic volume reduction. The thoracoscopic creation of a pleural tent is feasible and results in a duration of postoperative air leaks and hospital stays similar to that achieved with stapler line buttressing.     

Congenital chylothorax in siblings

We describe two cases of congenital chylothorax in siblings with important differences from previously described familial cases. Our findings support the likelihood of an autosomal recessive inheritance in some cases of this condition, rather than X-linked recessive inheritance, which has also been suggested. Autopsy findings from one of these cases and others previously described suggest that the pathophysiological mechanisms involved may be variable.     

Protection against myocardial ischemic/reperfusion injury by inhibitors of two separate pathways of Na+ entry

Critics of Kohlberg's moral theory today focus on the content of his theory and more specifically on its justice-orientated moral concept. This has led to the well-known 'justice-care debate'. The purpose of this article is to critically examine the validity of Kohlberg's moral theory for research in nursing ethics from a caring perspective (referring to the content) as well as from a cognitive-structural perspective (referring to the basic assumptions of the model). The analysis points to the usefulness and value of the cognitive-structural model to empirically study nurses' ethical behaviour; the content of Kohlberg's model, however, needs to be adapted by adding a caring perspective as well as some personal and situational variables. An adjusted version of Kohlberg's model is proposed and discussed.